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Growth of Strongly Biaxially Aligned MgB2 Thin Films on Sapphire by Post-annealing of Amorphous Precursors

A. Berenov·Z. Lockman·X. Qi·Y. Bugoslavsky·L. F. Cohen·M. -H. Jo·N. A. Stelmashenko·V. N. Tsaneva·M. Kambara·N. Hari Babu·D. A. Cardwell·M. G. Blamire·J. L. MacManus-Driscoll
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Abstract

MgB2 thin films were cold-grown on sapphire substrates by pulsed laser deposition (PLD), followed by post-annealing in mixed, reducing gas, Mg-rich, Zr gettered, environments. The films had Tcs in the range 29 K to 34 K, Jcs (20K, H=0) in the range 30 kA/cm2 to 300 kA/cm2, and irreversibility fields at 20 K of 4 T to 6.2 T. An inverse correlation was found between Tc and irreversibility field. The films had grain sizes of 0.1-1 micron and a strong biaxial alignment was observed in the 950C annealed film.

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A. Berenov, Z. Lockman, X. Qi, Y. Bugoslavsky, L. F. Cohen, M. -H. Jo, N. A. Stelmashenko, V. N. Tsaneva, M. Kambara, N. Hari Babu, D. A. Cardwell, M. G. Blamire, J. L. MacManus-Driscoll. 2001-06-14. Growth of Strongly Biaxially Aligned MgB2 Thin Films on Sapphire by Post-annealing of Amorphous Precursors. https://doi.org/10.1063/1.1424070

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